Thanks everyone.

She didn't have all that much in her accounts - maybe £2000 total - but I'm still surprised the bank allowed the thieves to withdraw ALL her money from TWO accounts at the same bank.

I'm not sure what will happen - hopefully the bank will reimburse her. She's expecting the police to visit her either tonight or tomorrow, she reported it to the police station when she found out what had happened when she'd gone to the bank to report her cards missing.